Cycles: OpenCL kernel split

This commit contains all the work related on the AMD megakernel split work
which was mainly done by Varun Sundar, George Kyriazis and Lenny Wang, plus
some help from Sergey Sharybin, Martijn Berger, Thomas Dinges and likely
someone else which we're forgetting to mention.

Currently only AMD cards are enabled for the new split kernel, but it is
possible to force split opencl kernel to be used by setting the following
environment variable: CYCLES_OPENCL_SPLIT_KERNEL_TEST=1.

Not all the features are supported yet, and that being said no motion blur,
camera blur, SSS and volumetrics for now. Also transparent shadows are
disabled on AMD device because of some compiler bug.

This kernel is also only implements regular path tracing and supporting
branched one will take a bit. Branched path tracing is exposed to the
interface still, which is a bit misleading and will be hidden there soon.

More feature will be enabled once they're ported to the split kernel and
tested.

Neither regular CPU nor CUDA has any difference, they're generating the
same exact code, which means no regressions/improvements there.

Based on the research paper:

  https://research.nvidia.com/sites/default/files/publications/laine2013hpg_paper.pdf

Here's the documentation:

  https://docs.google.com/document/d/1LuXW-CV-sVJkQaEGZlMJ86jZ8FmoPfecaMdR-oiWbUY/edit

Design discussion of the patch:

  https://developer.blender.org/T44197

Differential Revision: https://developer.blender.org/D1200

1 files changed, 51 insertions, 18 deletions

diff --git a/intern/cycles/kernel/geom/geom_object.h b/intern/cycles/kernel/geom/geom_object.h
index 7df71010232..40cbca243a7 100644
--- a/intern/cycles/kernel/geom/geom_object.h
+++ b/intern/cycles/kernel/geom/geom_object.h
@@ -123,9 +123,9 @@ ccl_device_inline Transform object_fetch_transform_motion_test(KernelGlobals *kg
 ccl_device_inline void object_position_transform(KernelGlobals *kg, const ShaderData *sd, float3 *P)
 {
 #ifdef __OBJECT_MOTION__
-	*P = transform_point(&sd->ob_tfm, *P);
+	*P = transform_point(&ccl_fetch(sd, ob_tfm), *P);
 #else
-	Transform tfm = object_fetch_transform(kg, sd->object, OBJECT_TRANSFORM);
+	Transform tfm = object_fetch_transform(kg, ccl_fetch(sd, object), OBJECT_TRANSFORM);
 	*P = transform_point(&tfm, *P);
 #endif
 }
@@ -135,9 +135,9 @@ ccl_device_inline void object_position_transform(KernelGlobals *kg, const Shader
 ccl_device_inline void object_inverse_position_transform(KernelGlobals *kg, const ShaderData *sd, float3 *P)
 {
 #ifdef __OBJECT_MOTION__
-	*P = transform_point(&sd->ob_itfm, *P);
+	*P = transform_point(&ccl_fetch(sd, ob_itfm), *P);
 #else
-	Transform tfm = object_fetch_transform(kg, sd->object, OBJECT_INVERSE_TRANSFORM);
+	Transform tfm = object_fetch_transform(kg, ccl_fetch(sd, object), OBJECT_INVERSE_TRANSFORM);
 	*P = transform_point(&tfm, *P);
 #endif
 }
@@ -147,9 +147,9 @@ ccl_device_inline void object_inverse_position_transform(KernelGlobals *kg, cons
 ccl_device_inline void object_inverse_normal_transform(KernelGlobals *kg, const ShaderData *sd, float3 *N)
 {
 #ifdef __OBJECT_MOTION__
-	*N = normalize(transform_direction_transposed(&sd->ob_tfm, *N));
+	*N = normalize(transform_direction_transposed(&ccl_fetch(sd, ob_tfm), *N));
 #else
-	Transform tfm = object_fetch_transform(kg, sd->object, OBJECT_TRANSFORM);
+	Transform tfm = object_fetch_transform(kg, ccl_fetch(sd, object), OBJECT_TRANSFORM);
 	*N = normalize(transform_direction_transposed(&tfm, *N));
 #endif
 }
@@ -159,9 +159,9 @@ ccl_device_inline void object_inverse_normal_transform(KernelGlobals *kg, const
 ccl_device_inline void object_normal_transform(KernelGlobals *kg, const ShaderData *sd, float3 *N)
 {
 #ifdef __OBJECT_MOTION__
-	*N = normalize(transform_direction_transposed(&sd->ob_itfm, *N));
+	*N = normalize(transform_direction_transposed(&ccl_fetch(sd, ob_itfm), *N));
 #else
-	Transform tfm = object_fetch_transform(kg, sd->object, OBJECT_INVERSE_TRANSFORM);
+	Transform tfm = object_fetch_transform(kg, ccl_fetch(sd, object), OBJECT_INVERSE_TRANSFORM);
 	*N = normalize(transform_direction_transposed(&tfm, *N));
 #endif
 }
@@ -171,9 +171,9 @@ ccl_device_inline void object_normal_transform(KernelGlobals *kg, const ShaderDa
 ccl_device_inline void object_dir_transform(KernelGlobals *kg, const ShaderData *sd, float3 *D)
 {
 #ifdef __OBJECT_MOTION__
-	*D = transform_direction(&sd->ob_tfm, *D);
+	*D = transform_direction(&ccl_fetch(sd, ob_tfm), *D);
 #else
-	Transform tfm = object_fetch_transform(kg, sd->object, OBJECT_TRANSFORM);
+	Transform tfm = object_fetch_transform(kg, ccl_fetch(sd, object), OBJECT_TRANSFORM);
 	*D = transform_direction(&tfm, *D);
 #endif
 }
@@ -183,9 +183,9 @@ ccl_device_inline void object_dir_transform(KernelGlobals *kg, const ShaderData
 ccl_device_inline void object_inverse_dir_transform(KernelGlobals *kg, const ShaderData *sd, float3 *D)
 {
 #ifdef __OBJECT_MOTION__
-	*D = transform_direction(&sd->ob_itfm, *D);
+	*D = transform_direction(&ccl_fetch(sd, ob_itfm), *D);
 #else
-	Transform tfm = object_fetch_transform(kg, sd->object, OBJECT_INVERSE_TRANSFORM);
+	Transform tfm = object_fetch_transform(kg, ccl_fetch(sd, object), OBJECT_INVERSE_TRANSFORM);
 	*D = transform_direction(&tfm, *D);
 #endif
 }
@@ -194,13 +194,13 @@ ccl_device_inline void object_inverse_dir_transform(KernelGlobals *kg, const Sha
 
 ccl_device_inline float3 object_location(KernelGlobals *kg, const ShaderData *sd)
 {
-	if(sd->object == OBJECT_NONE)
+	if(ccl_fetch(sd, object) == OBJECT_NONE)
 		return make_float3(0.0f, 0.0f, 0.0f);
 
 #ifdef __OBJECT_MOTION__
-	return make_float3(sd->ob_tfm.x.w, sd->ob_tfm.y.w, sd->ob_tfm.z.w);
+	return make_float3(ccl_fetch(sd, ob_tfm).x.w, ccl_fetch(sd, ob_tfm).y.w, ccl_fetch(sd, ob_tfm).z.w);
 #else
-	Transform tfm = object_fetch_transform(kg, sd->object, OBJECT_TRANSFORM);
+	Transform tfm = object_fetch_transform(kg, ccl_fetch(sd, object), OBJECT_TRANSFORM);
 	return make_float3(tfm.x.w, tfm.y.w, tfm.z.w);
 #endif
 }
@@ -296,7 +296,7 @@ ccl_device_inline void object_motion_info(KernelGlobals *kg, int object, int *nu
 
 ccl_device int shader_pass_id(KernelGlobals *kg, const ShaderData *sd)
 {
-	return kernel_tex_fetch(__shader_flag, (sd->shader & SHADER_MASK)*2 + 1);
+	return kernel_tex_fetch(__shader_flag, (ccl_fetch(sd, shader) & SHADER_MASK)*2 + 1);
 }
 
 /* Particle data from which object was instanced */
@@ -377,7 +377,7 @@ ccl_device_inline float3 bvh_inverse_direction(float3 dir)
 
 /* Transform ray into object space to enter static object in BVH */
 
-ccl_device_inline void bvh_instance_push(KernelGlobals *kg, int object, const Ray *ray, float3 *P, float3 *dir, float3 *idir, float *t)
+ccl_device_inline void bvh_instance_push(KernelGlobals *kg, int object, const Ray *ray, float3 *P, float3 *dir, float3 *idir, ccl_addr_space float *t)
 {
 	Transform tfm = object_fetch_transform(kg, object, OBJECT_INVERSE_TRANSFORM);
 
@@ -425,7 +425,7 @@ ccl_device_inline void qbvh_instance_push(KernelGlobals *kg,
 
 /* Transorm ray to exit static object in BVH */
 
-ccl_device_inline void bvh_instance_pop(KernelGlobals *kg, int object, const Ray *ray, float3 *P, float3 *dir, float3 *idir, float *t)
+ccl_device_inline void bvh_instance_pop(KernelGlobals *kg, int object, const Ray *ray, float3 *P, float3 *dir, float3 *idir, ccl_addr_space float *t)
 {
 	if(*t != FLT_MAX) {
 		Transform tfm = object_fetch_transform(kg, object, OBJECT_TRANSFORM);
@@ -520,5 +520,38 @@ ccl_device_inline void bvh_instance_motion_pop_factor(KernelGlobals *kg, int obj
 
 #endif
 
+/* TODO(sergey): This is only for until we've got OpenCL 2.0
+ * on all devices we consider supported. It'll be replaced with
+ * generic address space.
+ */
+
+#ifdef __KERNEL_OPENCL__
+ccl_device_inline void object_dir_transform_addrspace(KernelGlobals *kg,
+                                                      const ShaderData *sd,
+                                                      ccl_addr_space float3 *D)
+{
+	float3 private_D = *D;
+	object_dir_transform(kg, sd, &private_D);
+	*D = private_D;
+}
+
+ccl_device_inline void object_normal_transform_addrspace(KernelGlobals *kg,
+                                                         const ShaderData *sd,
+                                                         ccl_addr_space float3 *N)
+{
+	float3 private_N = *N;
+	object_dir_transform(kg, sd, &private_N);
+	*N = private_N;
+}
+#endif
+
+#ifndef __KERNEL_OPENCL__
+#  define object_dir_transform_auto object_dir_transform
+#  define object_normal_transform_auto object_normal_transform
+#else
+#  define object_dir_transform_auto object_dir_transform_addrspace
+#  define object_normal_transform_auto object_normal_transform_addrspace
+#endif
+
 CCL_NAMESPACE_END